Sitting behind a car at a stoplight recently, I learned the driver's political affiliation, sexual orientation, the college he attended, that his child was an honor student, and the number of his favorite NASCAR driver. All this from bumper stickers, and it was way more than I wanted to know. Runners aren't immune from this need to tell people about ourselves, except we put our message on our clothes. I started a bit of controversy a few years back by wearing a shirt that read, "I'm slow. I know. Get over it" for a story in The New York Times. Running purists thought I was demeaning the sport. I just wanted to share my perspective. Plus, it was funny.

Now that I do a lot of announcing at finish lines, I've seen thousands of runners wearing T-shirts that say who they are and what motivates them to run. Some shirts have an element of subtle anarchy and social awareness. Among my favorites in this category is, "I run like a girl. Try to keep up" and "On the seventh day God did an easy three." I also like shirts that tell me something about the wearer (e. g., "Will run for beer") or are self-affirming like, "In my dreams I'm a Kenyan." My all-time favorite shirt sums up a moment I've had at some point in each of the 45 marathons I've run: "This seemed like a good idea three months ago." It makes me smile every time.

One of my least favorites is "Pain is weakness leaving the body." Runners know pain is the body's way of warning you that you're doing too much and if you don't listen, you'll end up injured. Then there are the slogans that aren't entirely thought through. I've seen plenty of runners finish midpack wearing a shirt that declares, "Second place is the first loser."

My mission now is to promote the runner- as-billboard phenomenon. When you are one of 35,000 participants in a race, do yourself a favor and shout something out on your shirt. Make sure everyone on the sidelines knows why they're cheering. If you're running to make the world a better place, let them know. If you're running to make yourself a better person, let them know. Let's tell the world who we are, what we believe, and why it matters.

If nothing else, I want to encourage everyone who runs a race to put your name boldly on the front of your shirt. Put it there in large letters. You won't remember your number late in the race, but with any luck you'll still be able to remember your name. And when you hear your name, you'll be reminded of why you're there—and why it sounded like a good idea three months earlier.

After all, for most of us, the real reason we race isn't because we hope to land on the podium or claim an age-group award. We race to challenge ourselves, or in memory of a loved one, or for a charity, or for any number of personal and special reasons. All of those reasons (and all of those runners) deserve a moment to shine. So the next time I'm announcing at the finish line, I hope to see you proudly wearing a personalized shirt—so I can congratulate each of you by name.